Melanotan II Uncovered Your Essential Guide to Tanning, Libido Enhancement, and Smart Peptide Protocols: Proven Methods to Inject Safely, Monitor Melanotan vs. Astaxanthin for Glowing Skin Melanotan II synthetic tanning drug molecule, illustration Stock Image F029 9531 Science Photo Library Your body already makes a hormone that tells your skin to tan. Melanotan 2 is a synthetic peptide engineered to mimic that hormone but in a version that's more potent and Avoid nasal tanning sprays or nasal tanners entirely. These products promise an all over tan without sun exposure but they are unregulated, can be unsafe, and contain potentially risky substances like Melanotan 2.